This invention relates to a vehicle window glass antenna for receiving broadcast waves, which uses a transparent and conductive film coated on the window glass pane or interposed between two sheets of glass that constitute a laminated glass. The antenna according to the invention is particularly suited to automobiles.
It is known to provide the rear window glass of an automobile with a so-called window glass antenna which is made up of conductive strips disposed on the glass surface in a suitable pattern. However, it is difficult to acquire sufficiently high gains in receiving radio and television broadcast waves by such an antenna because the antenna has to be formed within a narrow area left above or below an array of defogging heater strips usually provided to the rear window glass.
Also it has been proposed to provide the windshield of an automobile with a transparent and conductive film to use it as an antenna for reception of broadcast waves as shown, for example, in JP-UM No. 49-1562. However, vehicle window glass antennas of this type are still under development and have rarely been employed in industrially manufactured cars. Thus far, few of these window glass antennas have exhibited sufficiently high gains in receiving both FM radio broadcast waves and television broadcast waves and have become comparable to conventional whip antennas about 1 m long.